Monitoring of patient's electrical characteristics using a single piece of equipment

Abstract

The invention relates to a method and a system for a medical monitoring system, in which method the functions of a patient are measured, and the change in the electric activity of the patient are observed. In the method, the electrocardiogram (EKG), electroencephalogram (EEG), and the impedance cardiograph signal (IKG) are being measured with one piece of measuring equipment.

1. A method for medical monitoring of a patient to obtain a plurality of different physiological signal data from a common electrode set, said common electrode set having four extremity electrodes and up to six additional electrodes, wherein said method comprises the steps of:
 attaching selected electrodes of the common set to the patient in a manner to obtain up to 5 lead EKG signal data using an electrode selection made from the extremity electrodes and at least one additional electrode; 
 attaching at least one of the remaining additional electrodes of the common set to the patient in a manner suitable for obtaining EEG signal data or IKG signal data, the attachment of the common electrode set to the patient simultaneously generating a plurality of different physiological and signal data in the common electrode set, the electrodes of the common set being connected to a selection switch (K); 
 operating the selection switch (K) for selecting one of: the selected electrodes of the common set or the remaining additional electrodes of the common set; and 
 obtaining from the physiological signal data in the electrodes selected by operating the selection switch, one of up to 5 lead EKG signal data or one of EEG and IKG signal data. 
 
   
   
     2. The method according to  claim 1  further comprising the steps of:
 attaching the remaining, additional electrodes to the patient in a manner suitable for obtaining EEG signal data; and 
 operating the selector switch (K) to select the remaining additional electrodes; 
 
     and obtaining EEG signal data from the remaining additional electrodes. 
   
   
     3. The method according to  claim 1  further comprising the steps of:
 attaching the remaining, additional electrodes to the patient in a manner suitable for obtaining IKG signal data; and 
 operating the selector switch (K) to select the remaining additional electrodes; 
 
     and obtaining IKG signal data from the remaining additional electrodes. 
   
   
     4. The method according to  claim 1  further comprising the steps of:
 attaching at least one remaining, additional electrode to the patient in a manner to obtain EEG signal data from the patient; 
 attaching at least one further remaining additional electrode to the patient in a manner to obtain EMG signal data from the facial region of the patient; and 
 obtaining EEG and EMG signal data from the electrodes attached to the patient. 
 
   
   
     5. The method according to  claim 1  further comprising the steps of:
 attaching remaining, additional electrodes to the patient in a manner to obtain EEG signal data; and 
 calculating, from the obtained EEG signal data, an index describing a depth of the anesthesia of the patient. 
 
   
   
     6. The method according to  claim 1  wherein EEG signal data is obtained and the electrodes used to obtain EKG signal data and the electrodes used to obtain EEG signal data include a common neutral electrode. 
   
   
     7. The method according to  claim 1  further comprising the steps of:
 determining impedance relations among the electrodes; and 
 ascertaining from the impedance relations the locations on the patient at which additional remaining electrodes are attached. 
 
   
   
     8. A system for medical monitoring apparatus comprising:
 a common electrode set including four patient extremity electrodes adapted to be attached to a patient (P) and up to six additional electrodes adapted to be attached to the patient (P), one of said additional electrodes being includable with said extremity electrodes in a first electrode set for obtaining EKG signal data and the remaining additional electrodes being includable in a second electrode set for obtaining EEG or IKG signal data; 
 signal conductors connected to each of said electrodes in the common electrode set; 
 a common measurement device comprising electrocardiographic (EKG) measuring equipment, electroencephalographic (EEG) measuring equipment and impedance cardiographic (IKG) measuring equipment; and 
 a selector switch (K) interposed between said conductors connected to the common electrode set and said measurement device for selecting the measuring equipment to receive physiological data from the first or second electrode set such that when the selector switch (K) is in a first position EKG signal data from the first electrode set is sent to the electrocardiographic measuring equipment, when the selector switch (K) is in a second position the additional electrodes provide a selected one of EEG signal data from the second electrode set that is sent to said electroencephalographic (EEG) measuring equipment and when the selector switch (K) is in a third position IKG signal data from the second electrode set is sent to said impedance cardiographic (IKG) measuring equipment. 
 
   
   
     9. The system according to  claim 8  further comprising:
 preamplifier means coupled to said additional electrodes, said preamplifier means having means coupled to selected ones of said additional electrodes for use in obtaining IKG signal data when said switch means is operated to obtain IKG signal data. 
 
   
   
     10. The system according to  claim 8  further comprising:
 preamplifier means coupled to said additional electrodes for determining impedance relations among the electrodes for use in ascertaining the locations on the patient at which the electrodes are attached to the patient.